The fatality rate from COVID-19 in the United States have exceeded the toll of the 1918 influenza pandemic, a milestone many scientists and health authorities say was preventable after the introduction of vaccines.

Deaths from the virus in the U.S. have soared to more than 1,900 a day on average for the first time since March this year, with medical experts saying the disease is targeting largely a distinct group: 71 million unvaccinated Americans.

Based on an analysis conducted by CNN, the average rate of deaths in the 10 least immunized states in the U.S. was more than four times higher in the past seven days compared to the rate in the 10 most inoculated states.

CNN used data provided by the Johns Hopkins University and the Centers for Disease Control and Prevention (CDC) for its evaluation.

The increasingly deadly turn of events has overwhelmed health facilities, delayed the return to the work places, disrupted the start of the school year, and demoralized healthcare personnel.

For medical frontliners, the fatalities combined with misinformation and doubt about COVID-19 have been "heart-wrenching and soul-crushing," according to Dr. Dena Hubbard, a pediatrician in Kansas City, Missouri.

Hubbard was in charge of critical care of infants who were born prematurely through cesarean section in a desperate effort to save their mothers, some of whom have died.

Some 22 patients died in one week alone at CoxHealth hospitals in the Springfield-Branson area, a figure nearly as high as that of all of Chicago.

West Virginia has recorded more deaths in the first three weeks of the current month at 340, compared to the previous three months combined. Georgia, on the other hand, has had an average of 125 fatality a day -- more than California or other heavily populated states.

The U.S. was in shock in December last year, when it was recording 3,000 deaths per day. But that was when nearly no one was immunized from COVID-19.

The U.S. reported more than 2,200 deaths from the virus on Tuesday, bringing its fatality total since the start of the pandemic to 676,000.

Meanwhile, the Biden administration said it will lift travel restrictions in November on immunized passengers from Britain, China, South Africa, Brazil, Iran and India.